[PATCH 4.14 071/190] mmc: sdhci-msm: Clear tuning done flag while hs400 tuning

Greg Kroah-Hartman
2020-06-19T16:38:10Z

From: Veerabhadrarao Badiganti <vbadigan@codeaurora.org>

commit 9253d71011c349d5f5cc0cebdf68b4a80811b92d upstream.

Clear tuning_done flag while executing tuning to ensure vendor
specific HS400 settings are applied properly when the controller
is re-initialized in HS400 mode.

Without this, re-initialization of the qcom SDHC in HS400 mode fails
while resuming the driver from runtime-suspend or system-suspend.

Fixes: ff06ce417828 ("mmc: sdhci-msm: Add HS400 platform support")
Cc: stable@vger.kernel.org
Signed-off-by: Veerabhadrarao Badiganti <vbadigan@codeaurora.org>
Link: https://lore.kernel.org/r/1590678838-18099-1-git-send-email-vbadigan@codeaurora.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/mmc/host/sdhci-msm.c | 6 ++++++
1 file changed, 6 insertions(+)

--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -861,6 +861,12 @@ static int sdhci_msm_execute_tuning(stru
msm_host->use_cdr = true;

/*
+ * Clear tuning_done flag before tuning to ensure proper
+ * HS400 settings.
+ */
+ msm_host->tuning_done = 0;
+
+ /*
* For HS400 tuning in HS200 timing requires:
* - select MCLK/2 in VENDOR_SPEC
* - program MCLK to 400MHz (or nearest supported) in GCC